A refrigerator is an apparatus for keeping foods stored in a refrigerator compartment and a freezer compartment fresh by using cooling cycles provided by a compressor, a condenser, a capillary tube (or an expansion valve) and an evaporator.
The evaporator generates cold air in a cooling chamber, and the cold air is supplied to the refrigerator and the freezer compartments through a refrigerator compartment supply duct and a freezer compartment supply duct. Meanwhile, a fan induces the cold air into the refrigerator compartment and the freezer compartment. The cold air that has cooled down the refrigerator compartment and the freezer compartment returns to the cooling chamber through a refrigerator compartment return duct and a freezer compartment return duct.
The fan may be driven while the refrigerant circulates during cooling cycles using a compressor. However, when the fan is not driven, the cold air in the cooling chamber may flow back into the refrigerator compartment return duct or the freezer compartment return duct. Accordingly, the moisture in the refrigerator compartment may become frozen in the refrigerator compartment return duct and block the duct.
Such problems frequently occur in a bottom mounted freezer (BMF) refrigerator, in which the freezer compartment is under the refrigerator compartment. Such problems may be more severe in a small BMF refrigerator, in which the fan is placed in the refrigerator compartment, rather than in the freezer compartment.